Blocking Behaviors of Broadcast Switching Networks in Random Traffics

Date of Submission: 
January 21, 1998
Report Number: 
This paper investigates 3-stage Clos networks for broadcastcommunications and their blocking probability with randomtraffic andrandom routing strategy. Middle and output stage switchesof thenetworks are assumed to be able to duplicate messages, butinputstage switches are to lack of the fanout capability. Eventhough thesimple routing strategy theoretically requires anexcessively large number ofmiddle switches to provide nonblocking paths to compatiblerequests,the probabilistic model gives an observation that theblockingprobability is dramatically decreasing and then approachingto zero asthe number of middle switches is increasing so that it canpracticallyafford nonblocking behaviors with much less middle switchesthan theone that the nonblocking networks required. We alsocorroborate theanalytic model by performing simulations on low mean fanoutto obtainindependent destination set.